bug#11308: 24.1.50; More completion confusion

[Drew Adams]

Nothing new.  Just another example of how completion with multiple
styles chained together can be confusing.  At least that's what I
suppose the culprit is (without looking).
 
emacs -Q
 
M-x find-library RET isearch.e
 
Put point at bol (i.e. on/just before the `i') and hit TAB.  You get
(only) the completion isearch.elc.  And point is not moved to eol: it
stays where it was.
 
Or put point on `.' - same thing.  But quicker - when point is on the
`i' it takes a while.
 
But putting point on or after the second `e' gives isearch.el as the
only completion.  Likewise, point on the `h', the `c', the `r', the `a',
and the `s'.
 
But first complete with point at bol (on `i'), then remove the final
`lc' and move point to the `s'.  TAB then completes to isearch.el, as
before, but this time with the message [Complete but not unique], which
was not shown before with point at the same place (on `s').
 
Well not quite.  _Sometimes_ you will see [Complete but not unique] when
you follow that recipe.  Sometimes you will not.  Depends on the tide
perhaps.
 
Hardly what I would call "least surprise".  YMMV.
 

In GNU Emacs 24.1.50.1 (i386-mingw-nt5.1.2600)
 of 2012-04-19 on MARVIN
Bzr revision: 107968 monnier@iro.umontreal.ca-20120419220225-gijdcbfxuiqy5dhb
Windowing system distributor `Microsoft Corp.', version 5.1.2600
Configured using:
 `configure --with-gcc (4.6) --no-opt --enable-checking --cflags
 -ID:/devel/emacs/libs/libXpm-3.5.8/include
 -ID:/devel/emacs/libs/libXpm-3.5.8/src
 -ID:/devel/emacs/libs/libpng-dev_1.4.3-1/include
 -ID:/devel/emacs/libs/zlib-dev_1.2.5-2/include
 -ID:/devel/emacs/libs/giflib-4.1.4-1/include
 -ID:/devel/emacs/libs/jpeg-6b-4/include
 -ID:/devel/emacs/libs/tiff-3.8.2-1/include
 -ID:/devel/emacs/libs/gnutls-3.0.9/include
 -ID:/devel/emacs/libs/libiconv-1.13.1-1-dev/include
 -ID:/devel/emacs/libs/libxml2-2.7.8/include/libxml2'